Quantitative Chemestry Eg Q

Question 1

2-H2 + O2 ➡️2-H2_O

How many moles of oxygen react with 10 moles of hydrogen?

Answer 1

Ratio,
(2:1)
=5mol

Question 2

TiC + 4Na -> Ti + 4NaCl

a) How many moles of sodium react with 4 moles of titanium chloride?

b) How many moles of titanium are made from 2.5 moles of titanium chloride?

Answer 2

A) 16
Ratio 4:1
B)2.5
Ratio 1:1

Question 3

2KCI03 -> 2KCI + 302
a) How many moles of potassium chloride are formed when 10 moles of potassium chlorate decomposes?

B) How many moles of oxygen are formed when 3 moles of potassium chlorate decomposes?

Answer 3

A)10mol
1:1

B)4.5mol
2:3

Question 4

What mass of oxygen is needed to react with 10g of hydrogen?
2-H2 + 02 ➡️ 2-H2_0

Answer 4

80g
2:1 ratio

Question 5

What mass of aluminium can be formed from 1 kg of aluminium oxide? give your answer to 3 significant figures.
2-Al2_03 ➡️ 4-Al + 3-02

Answer 5

529g
1:2 ratio
1kg=1000g
Disregard big numbers

Question 6

1.2g of magnesium (Mg) reacts with 0.8 g of oxygen (O,) to make 2.0g of magnesium oxide (MO). Use this information to deduce the equation for this reaction.

Answer 6

Question 7

6.8 g of hydrogen peroxide (H202) decomposes into 3.6 g of water
(H,O) and 3.2 g of oxygen (02). By calculating molar ratios, deduce the balanced equation for this reaction.

Answer 7